Actually, according to RevRul 93-86, Ltr Rul 9536012 (PLR) 6/7/95, ISP 145 and Analysis Sec 27.3, "If employment away from home in a single location initially is realistically expected to last for 1 year or less, but at some later date the employment is realistically expected to exceed 1 year that employment will be treated as temporary (in absence of facts and circumstances indicating otherwise) until the date the realitic expectation changed. Thus, if the employment is away from home and temporary, it meets the business connection requirement."

Additionally, another of the "tests" you have met..."If it is found that the employee has a tax home (i.e., the employee has either a regular or principal place of business or, failing that, an abode in a real and substantial sense)..."

My opinion would be you can take the expenses up to the time you were informed you had to extend your stay.